Weight determining device



Nov. 16, 1954 R. T. POUNDS WEIGHT DETERMINING DEVICE 5 Sheets-Sheet 1 Filed March 3. 1948 INVENTOR RICHARD T. POUNDS.

W ATTORNEY Nov. 16, 1954 R. T. POUNDS WEIGHT DETERMINING DEVICE 5 Sheets-Sheet 2 Filed March 3, 1948 N GE RXCHARD T. POUNDS.

ATTORNEY Nov. 16, 1954 R. 1-. POUNDS v WEIGHT DETERMINING DEVICE 5 Sheets-Sheet 3 Filed March 3, 1948 INVENTOR RICHARD T. POUNDS ATTORNEY Nov. 16, 1954 R. T. POUNDS WEIGHT DETERMINING DEVICE 5 Sheets-Sheet- 4 Filed March 5, 1948 mm m9. g mm m W m Mm -fiw w IIIFII m wOE NOE 9 9K i I /1 fl l I I. I. 0 III! OO HI m Kw 8a m T mmi @OE w n 0 6mm wmO ATTORNEY NOV. 16, 1954 T, POUNDS WEIGHT DETERMINING DEVICE 5 Sheets-Sheet 5 Fil ed March 5, 194a *w wI INVENTOR RICHARD T. POUNDS. BY A'ITQRNEY United States PatentOfitice WEIGHT DETERMINING DEVICE Richard T. Pounds, Westport, Conn., assignor to American Machine & Foundry Company, a corporation of New Jersey Application March 3, 1948, Serial No. 12,705 19 Claims. (Cl. 73-67) This invention relates to weight determining devices, more particularly to devices which are sensitive and fast enough to weigh material or objects of relatively small weight, such as cigarettes, at relatively high speeds, preferably on the order of several hundred weighings per minute.

Thus one of the main objects of the invention is to weigh the objects in a very short interval of time.

A further object of the invention is to determine the weight of the object to be weighed by measuring the variations in the time required by a vibratory structure supporting said object, to traverse a predetermined portion of one vibration cycle. For this purpose the object to be weighed may be supported on a structure deflected from a neutral adapted to vibrate when it is position. The vibration of this structure serves to control the flow of current in an electrical circuit during a predetermined portion of one vibration cycle of the structure. Variations in the weight of the object supported on said structure will be reflected in diflerences in the electrical current flowing in said circuit and there- 'by permit determination of the weight of the object to be weighed.

A further object is to make this weight determining device insensitive to extraneous vibration. For this purpose the time required by the vibratory structure or sampling member supporting said object, to complete said predetermined portion of a vibration cycle, is compared with the time required by a vibratory structure or standard member having a vibration frequency approximately equal to that of the sampling member when the latter supports an object of the required weight. Accordingly, if the sampling and standard members are vibrated at the same time while the object to be weighed is supported on the standard member, variations in the vibration frequency of said sampling member will correspond to variations in the weight of said object despite variations in extraneous vibration. Therefore, varia tions in these two time intervals can be determined to obtain the weight of the object being weighed.

Other objects and features of the invention will appear as the description of the particular physical embodiment selected to illustrate the invention progresses.

In the accompanying drawings this specification, like characters of reference have been applied to corresponding parts throughout the several views which make up the drawings;

Fig. 1 is a side elevation of a weighing apparatus embodying my invention.

Fig. 2 is a plan view thereof, the top of the apparatus being broken away to expose certain parts underneath the same.

Fig. 3 is a wiring diagram of the electrical circuit employed for measuring the time required by the structure, supporting an object to be weighed, to complete a predetermined portion of one cycle of vibration.

Figs. 412 show the wave forms which may be observed b connecting an oscilloscope to the pin-jacks I-l to J-7 inclusive, shown in Fig. 3.

Fig. 13 shows an alternative method for measuring the time required by the vibrating structure to complete a predetermined portion of one cycle of vibration.

Fig. 14 shows a conventional recording ammeter.

Reference will now be made to Figs. 1 and 2 of the drawings which illustrate suitable apparatus for deter mining the weight of an object in a time interval corresponding to that which would be available if the unit which form a part of.

,- scription thereof is deemed unnecessary.

' shaft 23 which is rotatably mounted I electrical circuit 2,694,310 Patented Nov. 16, 1954 were operating at a speed of approximately 600 weighings per minute.

This apparatus includes a base plate 1 and a top plate 2 formed of any suitable material and connected by a pair of corner posts 3 at one end of these plates and a pair of corner posts at the other end of these plates. Intermediate the posts 3 is a post 7, and intermediate posts 5 is a post 8.

Two resonant structures and 30 are provided, which are supported in a manner which will now be described. The upper end of structure 10 projects upwardly through an aperture in plate 2 and is equipped with a spring clip 11 for holding individual objects such as for example cigarettes. Structure 10 is referred to as the sampling member. The structure 30 has a predetermined mass and is regarded as the standard member. The total mass of the sampling member is such that when loaded with a cigarette of ideal or required weight, its total mass is approximately equal to that of the standard member.

The structure 10 is supported resiliently by pairs of strings 12 and 13 which may be made of piano wire or other suitable flexible material. The piano wires 12 and 13 are anchored at their outer ends to the corner posts Sand secured at their inner ends to the upper and lower ends of structure 10. The inner end of string 14, which is also formed of piano wire or other suitable material, is secured to the shield 17 which is formed of electrically conductive material and rigidly secured to structure 10 and forms a part thereof. A tension spring 18 secured to the outer end of piano wire 14 is anchored on a length of suitable flexible material such as piano wire 19 which passes over a guide 20 secured to the post 7. The wire 19 is secured to the inner end of a in post 7 and provided with a knob on its outer end. A plate 27 is suitably secured to post 7 by a screw 26. Plate 27 is provided at its upper end with an aperture through which projects a sleeve 28 which is secured to shaft 23, the knob 25 being secured to sleeve 28. A flange 29 on the inner end of sleeve 28 is engaged by the upper end of plate 27 and thereby held against a flattened portion 7a on post 7. Upon turning the knob 25 the vibration frequency of structure 10 may be regulated to correspond to the vibration frequency of the structure 30.

Structure 30 is resiliently supported by pairs of strings 32, 34 and a string 36 which may be formed from piano Wire or other suitable flexible material. The piano wires 32 and 34 are secured to the upper and lower ends of structure 30 and anchored to corner posts 3. One end .of piano Wire 36 is connected to the shield 31 which other end to the lower end of piano wire 40 passing over a guide 42 secured to post 8. The upper end of piano wire 40 is secured to a shaft 44 carrying a knob 46. Since the construction of knob 46 and shaft 44 is similar to that of knob 25 and shaft 23, further de- It may be noted that by turning knob 46 the vibration frequency of structure 30 may be regulated.

The electromagnets 50 and 52 are secured to the base plate 1 and underlie armatures 54 and 56 secured to the structures 10 and 30 respectively. When the electromagnets 50 and 52 are energized by an electrical circuit which will be presently described, the armatures 54 and 56 are attracted and held thereon whereby the structures 10 and 30 are deflected from their neutral position.

" Upon deenergization of electromagnets 50 and 52 the structures are permitted to vibrate through one cycle after which the electromagnets are reenergized to lock the structures 10 and 30 in their deflected positions. The

provides means for measuring individually, the time required for structures 10 and 30 to traverse a predetermined portion of one cycle of vibration and for comparing the individual time measurements for the purpose of weight determination.

Referring now to Fig. 3 of the drawings wherein a suitable circuit for this purpose is illustrated. A signal of constant frequency, suchas"400 kil'ocycles;"is-geueF ated by a vacuum tube oscillator O and fed simultaneously into the grids of two pick-up circuit amplifiers, eachof which. is. aSSOGiZtt6d1Wlthn0n6S of thezistructures or 30. This is indicated by the legendi'.'lnput':

(40O kc.) onv the control grid? of. the; amplifierttube VT-lx in Fig. 3. For simplicity. only;onez.circ.uit;. which is..:connected to the. coils.L-lA;.LdBglrZAaand 11-31%.

adjoining. the shield-17 of structure 1:10,; is; ==shown.. This:

circuitzis-also connectedrto-the electromagnetr 5.0.: The other circuit is a duplicate thereof and.is;-conne.eted:to. the; coils; L-4A, L-4B, L'T5A2 and:v LT6A" adjoining-{the shield-.31; of structure 30; andithe electromagnet 52..

The .400 he signal ;is :amplified -by the;tubefVT-.1iwhose;.

output is; divided by a split circuit'garrangement consisting of.:the coils. L1A;; I;1B on; one. side; of shield; 17 and coils L2A. and .L3A, onthe;other-;'side: of shield 17 and fedi; into a dual' rectifier-VT 2. Rectifier VT-2. is a doublediode -rectifier tube whose: cathodes are. connected to'condensers C1; and-:CZJ. The output-of this rectifier, whosepeak voltage-may have ;any.. suitable; potential such as; 100. volts indicated-in: Fig; 3, is;deliv,eredtoa: filter consisting of a coil L4 and condenser C4.

The physical relationship: between; the: coils. L-lA, L 13, .L-ZA and .L.3A and-shield 17 issuchthat when the structure 10 is in'its meanyor neutral position, theupper. and-lower edges of shield 17.- are; aligned with the axes of'-.these coils. and. equal voltages are. developed across coils. L1-2Aiand L-3A. Whentheshield 171's displaced. in: a downward direction,,- agreater voltage-is.

developed, across .coi1;L.-2A while-.th atacrosscoil. L3A isireduced. Ifv the shield is ,moveddn an upward. direction, the reverseis true.

Since thezvoltages developed:across. coils L2A' and L3A are impressedon the; anodes .ofsections- VT2A put: appears across-their resistive; cathode load. However, this load is also. split, the: output of VT;2A. being developed across resistor.- R-l: while 'VT-2B developsits voltageacross resistor R-2. Itwillbe-notedthatthese twoload resistors develop potentials of. oppositesign and, therefore, the. resultant voltage: appearing at the circuits outputis the algebraic .sumof the two. Since VT-ZA develops positive. voltage andVTj-2B develops.-

negative voltage,(as viewed from .the, output), .the re.-v

sultanh. when the shield. 171is .aLmeanposition, equals connected 7 to ,a source of direct: current of some rritable voltage suchdas +250. volts-,as indicated by the legend.

+250 v. in Fig. 3. The grid-of. tube VT-9is also connectedto theoutput of, thetube IT-2t.

If, the structurezltlismanually depressed, the .proper potential will be applied to the. gridof; tube @VT -9 to permit current to flow through; itsgplate circuit whenthe' switch S-in the. cathode circuittisclosed. Therefore, the:

electromagnet 50z-will be energized, whilestructure 10 is depressed, when the switch: Stinuthe cathode circuit of tube-VT-9 is closed1by-acam-60 mounted on a revolving shaft 62. The structure 10 'will'then be retained in its downwardly deflected. position until the switch S is opened by cam 60.

The other circuit, which'isconnected to the electromagnet 52 andthe coilsL-AA, L4B, L'5A and L-6A, which correspond to coilsL-IA, L-lB, L-ZA and L-3A, is providedwith a triode amplifier tube (not shown) corresponding to tube VT.'9; This tube also has an anode connected to the electromagnet' 52'anda suitable source Of'dIICCt current, and a-gridconnected to the output of a-dual rectifier tube (not'shown) corresponding tothe tubev VT-Z. When the structure 30 is' manually depressed to engage .the armature 56. with electromagnet. 52, .the structure 30 will be retained inits downwardly deflected position upon closing of the cathode circuit of this.:tube by the-same switch=SL 7' I lead ofwhich is connected,to,.a.,supply.line.W which is Time measuring circuit The time measuringcircuit, which will now be described, includes a saw tooth, wave generator tube VT-3 whose control grid receives single cycle sine wave input from the pickup circuit (Fig. 3) through a one megohm series resistor R3. The positivecomponents of the input on the control grid are clipped by the voltage drop across resistor R3:'and'the ou tput voltage of tube VT-3assurnes a form which would be a square wave of the type indicatedrby B in'Fig...5, .if' condenserTC-l. were not present inthe: plate-2 circuit of .tubeyVT.3. The time constant of the plate circuit (which includes the resistor TR-l and condenser TC-l) is chosen to allow a rise of plate potential toapproximately volts during a predetermined portion of .the time interval required for one cycle of vibration of structure 10. The resultant wave form displays a saw tooth characteristic indicated by the line B in Fig, 6. The shape .of this waveform may be determined "by connecting anoscilloscopeto jack; 1 3.

' The tube VT 4: constitutes a delayed" voltage amplifier, short-pulse square wave generatorand phase-inverter. The cathode of -'tube'*VT4"is* biasedhighly positive 'by a voltage" divider RD -1 RD"2connected to a supply of direct current of some suitable voltage such as l75"volts as-indicated ir'r-Fig; 3. Thecontrol gridof tube VT is connected to the anodeoftube. \IT-Z: through a. grid resistor Y R 4; Therefore; tubejVT-A -is' operative only when.its-grid=- -voltage-* approachesor'zexceeds the hired cathode potential. This-potentialis'adjusted to such a value that-the-grid2 prevents plate current flow until the saw tooth pattern (-Fig; 6) has grow-n:forapproxirnately .025 second to'a volt'ageindiea-ted by the line C in Fig; 6; The plate potential oli tube V,T--3' then-continues to increase until' it' rea'ches its-peakvoltageindicated-by the line=- D in Fig. 61 during-this time at -cathode potential due' to the grid current flowing -through resistor R-4, and'the plate current iri-tube V-T -4 -fiows-during this interval of time bythelinesaE-I and E-Z- The output oftube VT-d assumes: a square wave characteristic (Fig. 8-) whose minimurn and peak voltages are indicatedby the dimension-.linesEre and Er in Big. 7. In-Fig. 7 E1 indicates the'point at whichithe control grid of-tube VT4-begins toexercise control of its plate; current, and E2 indicates the peak of the excitation signal; I'n Fig. 3 Rs-is ahigh resistance inserieswiththe anode of= VT-4. The waveform of the-.output of tub'e VT-4 may be'determined by connecting:an'oscilloscopeto the jack J-4i (Fig. 3) connected tothe-anode of VT-4.

The output of tube .VT4"is coupled to the control grid of tube VT;--5. through. the condenseruC-S;

The ttube- V\Ti5; constitutes. a short interval sawtooth generator; .Timing.resistor.TtRellconnectsthe anode of tube VT-5 to;the.250';volt.supply-. line W, and timing condenser; TC2:is' :.connected pfromzthe anode of tube .VT-S to-.ground:' Themontrol :gridotftube VT5I is normally biased; for maximumplate'currenbflow since it isconnected through a resistonK-Ssto-lhe.supply lineW, resultinggin"minimumipotentiahacrosscondenser TC2. It may be noted that the plates or anodes' ot the=tubes VT-6 and are.;also*.connected:to thesupply line W. When thecontrol grid:;of-tube *VT..5:receiveszthe square wave input from the tube VT-4 (Fig. 9), its output: would appear; asshown: at Eig..10-ih:condenser TC2 were disconnected: DUBIOIhti presenceofcondensenTC-2 a saw toothgpat-ternzis developed. (Fig.;: 1.1).

The cathode circuit of the voltmeter reetifiertube VT-6 hasanozdirect connectionto ground .-with the result that anyaplate current flow results in a charge accumulating on condenser SC, connected: between itscathode and grounds. Atthe-start-of an operation cycle, condenser SC ispresumedtohave'been discharged-as will be-described.

a potential condensersG-will be somewhatgre'ater than thetpotential The grid= of" tube VT-'4 remains ace-1,310

as measured from the anode of VT-S to ground. When the grid of tube VT-6 is excited by the saw tooth pattern output of tube VT-S illustrated in Fig. 11, the condenser SC is charged in a pattern, which is illustrated in Fig. 12. The leading edge of this pattern resembles that of Fig. 11. However, at the end of the pulse the grid of tube VT-6 is quickly returned to a much lower potential than its cathode, and the plate current of tube VT-6 is completely cut off while the peak charge remains on condenser SC. The line A in Fig. 12 shows the charging interval on condenser SC, while the line B illustrates the steady state of the charge thereon. The discharging of the condenser is illustrated by the line CD in Fig. 12.

The tube VT-7 serves as a cathode follower voltmeter for measurement of the charge on condenser SC. The grid of tube VT-7 is connected directly to condenser SC, and its cathode is connected through a resistor RK to ground. The voltage appearing across the cathode resistor RK is, therefore, always proportional to the charge on SC within the limits permitted by the anticipated conditions. A micro-ammeter A, which is provided with a series resistor RA, is connected to the cathode end of the resistor RK. Micro-ammeter A is utilized as a voltmeter and is returned to a suitable comparison voltage source. In the particular embodiment of the invention exemplified herein, the comparison source is a voltmeter tube similar to tube VT7 and connected in an identical time measuring circuit, which measures the time required for the structure 30 to complete a predetermined portion of one vibration cycle while the structure 10 is completing a similar portion of one vibration cycle. However, if it were so desired, the structure could be dispensed with and the actual comparison source could be a steady known voltage. If a continuous record is desired, a conventional recording ammeter such as RA shown in Fig. 14 could be employed instead of the micro-ammeter A.

The tube VT-S forms the discharging circuit for the condenser SC. The grid of tube VT-8 is normally biased highly negative, causing its plate circuit to reflect infinite resistance to ground. When condenser SC is to be discharged, a positive bias is applied to the grid of tube VT8 from a suitable source of a direct current connected thereto through a shunt cam switch (not shown) indicated by the legend From shunt cam switch to +100 v. in the Fig. 3. This switch may be similar to the switch S and suitably closed by a cam similar to cam 60 at the end of the cycle of operation. The plate circuit then becomes conductive, discharging condenser SC. The slope of the discharge curve is shown between points C and D of Fig. 12. The rise of the curve after point D is the recharging of condenser SC to the cut-off point of tube VT-6.

The cam 60 is mounted on a shaft 62 which is suitably driven in timed relationship from a shaft 64. A sprocket 66 on shaft 64 is driven by a sprocket chain 68 from a suitable source of power (not shown). A crank disk 70 on shaft 64 is pivotally connected to one end of a connecting rod 72 whose other end is pivotally connected to a pusher 74. The pusher 74 reciprocates on the base 76 of a magazine 78 containing a supply of cigarettes to be weighed and serves to insert individual cigarettes between the top of the structure 10 and the clip 11 when the structure 10 is held in deflected position.

The cigarette thus inserted under clip 11 will be weighed when the switch S is opened to deenergize electromagnet and permit vibration of structure 10. The structure 30 will be permitted to vibrate simultaneously with structure 10 upon deenergization of the electromagnet 52 in the same manner. Upon reading the micro-ammeter A a direct determination of the weight of the cigarette inserted under clip 11 may be made, if the ammeter is calibrated for the various weights of the cigarettes to be weighed.

The armatures 54 and 56 will reengage the electromagnets 50 and 52 at the end of the vibration cycle of the structures 10 and 30. The switch S is reclosed by the cam during the charging period of condenser TC-l, while the grids of tubes VT-3 and VT-9 are highly negative and their anode currents cut oif. Therefore, as soon as these grids turn positive at the end of the timing period, magnets 50 and 52 are reenergized and will reengage and lock armatures 54 and 56 at the end of the vibration cycle.

In the next cycle of operation the delivery of the next cigarette underneath clip 11 by the pusher 74 will eject the preceding cigarette from underneath the clip .11 and permit the same to roll down upon the plate 2, as illustrated in Fig. 1. of the apparatus on a relatively plate 2.

Following is a descrip the circuit shown in Fig.

It should be noted here much larger scale than the part 3 and their functions:

that that part situated below frame plate 2 is shown above tion of the principal parts of In Fig. 13

Diode supply pick-up coil Plate inductance of t'fiii'vi fifiiirb'n mately 1 mh.)

Plat; coupling coil (air core) o Diode inductance for Positive output Diode supply pick-up coil Diode inductance for Negative output of tube VT2.

R. F. choke, filters R. F. components from time measuring circuit.

Diode load for Positive output of tube V'I2 Diode load for Negative output of tube VT-2.

Voltage divider. Determines tripping point of V'I4.

Timing resistor. In combination with condenser T0 determines slope of saw tooth curve developed by tube VT-3.

Cathode by-pass condenser ior tube V'I4 Peak charge storage condenser. Capacity used in present embodiment of invention may be /6 mid. to allow storage for comparatively long intervals.

Timing resistor. In combination with condenser TCQ determines slope of saw tooth curve developed by tube VT-5.

is illustrated a modified form of the invention determined portion of one cycle of vibration of the tures 10 and 30, ture 10, and inte weight of this cigarette.

is employed in conjunctio suitable light source, an op The light system includes a lens 106 which directs a through a narrow slit in di opening 10011 in a shutte cell 102.

The light in place of the shield an opening jected on to the neutral when a cigarette is supported on The circuit shown in F shutter is mounted on the structure 10 17. Shutter 100 is provided with iiferences required for a prestrucstrucrpreting the variations in terms of the n with a photoelectric cell, a tical system and a light shutter. an incandescent lamp 104 and beam of light from lamp 104 aphragm 107 and through the r 100 on to the photoelectric 100a through which the light beam is prothe photocell 102 when structure 10 is position shown in Fig. 13.

100a is so arranged that the photocell 102 will be i nated during a selected portion of one cycle of vib of structure The breadth of 0 upper edge will exp cell 102 when the its vibration cycle.

illuminated structure moves up to the cen until the upper edge of the opening of the vibration cycle.

basis of measurement of megohm resistor are substituted for the oscillator the circuit shown in Fig. 3, the coils L-2, L2A, tube VT-l,

cuit consisting of R-1, R-2,

The circuit shown in Fi manner hereinafter described to shown) including a photocell si and controlled by a light system and shutter (not similar to that L-3 and L3A, the shield The op above ening llumiration pening 100a may be such that its ose the light beam and illuminate ter of In this case the photocell will be This time the weight g. 13 is similar to that shown photoelectric'cell 102 and a 10 O of L-lB,

17, the amplifier rectifier VT-2 and its associated output cirshown in Fig. 13. The shutter shown) may be mounted on the structure 30 in of or upon light beam to illuminate the p The anode of photocell 102 is connected to the control,

the extension 31 C-1, C-2, L-4, C-4 and g. 13 is connected in a a duplicate circuit (not milar to photocell 102 shown) (not place and similarly expose the hotocell (not shown),

ama eur grid-"of Ctube V13 3;

voltsas indicated by. heJegendim-Fig; 13. tube VT-9 is also connected to this source current 1" through; the-esame xre'sistorr The. cathodeof photocell 1021 is suitablyii' biasedaias. indicatediiby; the legen 100 v. in Figr 13.

While the switch SP in the plate circuit of tube VT 9 is closed by the cam 160, which is mounted on revolving shaft'-162,- theelectromagnet-Sflw will be energized and will retain the structure.i10,.-(Eig s,,-,1- and.2) in its down-- wardly deflected position keeping the. light: beam cut off. Whenc'the cam-160permits the switchSP'to open, the electromagnet 50a willlbeid'eenergized.and the structure 10 will? vibratethrough': .onec..cycle1 of vibration. electromagnet' 50a-is-normalIy :energizedto attract and holdzthe armature 54 on structure. tain the latter. in.its downwardly-deflected position.

When the photocellis illuminatedduring the vibration of shutter 100 with structure .-10;.,the anode current of tube VT-3 .is .immediately. .cut. off, andv the tubes VT 3,

Th5: resulting readingmoni thea ammeter =AP indicates the weight ofthe cig'arettesupported on! structure 10. Ammeter; AP connection with; Fig; (not shown) which is aduplicate of th'e circuit ust described; If desired; aconventional recording ammeter RA shown in Fig.2; 1145'c.0'u1dbe employed in place of the ammeter. AP. to. produce.a. .continuousrecording.

In theidescription-roff thevoperation of the vibrating vibration as long as'this amplitude' isrlimited to a range.

within which' the -force:tending to restore the structure to neutral is substantially.proportional to the displacement from neutral; I could have chosen a position either'belowor above the 'neutral'position as-a reference point for the beginning and end" of the timing period, but in aStlCh a-case-the':.-lengthof'the period would no longer be independent'of the amplitude. I, therefore, prefer to use the neutral position as a reference point;

If the final charge oncondenser SC and the resulting voltage acrossresistor RKis comparedwith a fixed voltage,- extraneousvibrations imposed on the entire frame willhavean effect-on thereading, because'the timed periodwillbe lengthenedorshortened'depending on the phase relationof the vibration of structure 10" and the extraneous vibration. If, however, this charge is compared with one obtained in a similar manner from another vibrating structure, which-is releasedsimultaneously with the first and-subject to the-same external vibrations, they will both'be affected to'the same-degree, and the reading will be substantially inde endenvof extraneous vibration. Therefore, I prefer to use the twinstr-uctures iii-and 34), which are released simultaneouslyby cam-operated switch S;

The invention above described may be varied'in construction within the scope of the claims, for the particular deviceselected todll'ustrate the invention is but one of many possible embodiments of thesame. The invention, therefore; is not to;be -restricted to the precise details of the structure 1 shown and described.

What is claimedis':

1. In a weighing apparatus; the combination with a vibratory device adapted to vibrate when deflected from a neutral position, asupport' carried by said device and adapted to carrymaterial to'be weighed whereby variations in the massof the material carried'on said support will'varythevibrationfreqneney of said device, mechanis'in for deflecting said' 'device from a neutral position each time-mate'rialhas-been placed' on said'support and releasing-"the same to permit a single cycle of vibration thereof; and an instrument for determining the time inter- Theaanode t of; photocell ltlil i istconenected' through a lt) megohmiresistor: to a suitablersourceiof 'directr current having a suitable zvoltage :such .as +20 The grid-.of' of .direct' The- 10 and thereby mainis conneetedt to time circuit described in 13j-and3'also;'tothe other circuit va1: b etween1themoment: said device crosses saidaneu'ti'ai. position;each.;time=,materialis placed .on saidzsupportandii subsequently ICtlll'IlS"It0. said neutral 1 position.-

2. In aweighing. apparatus, .the.:combination-.with-i a structure adapted to vibrate when deflected .fromazneuw tral position, a.support.onsaid structure adapted to carryr material to be .weighed whereby variationsin the. mass of the material. supportedthereon will vary the period of vibration thereof, means for deflectingasaid structures.

from its neutral position and releasing thesame to permit vibration thereof: each. time material. to be weighed-1s. placedon saidsupport, adevice responsivetovariations; in the time required by SaIdZSUUCUlIGIO complete. a pret determined portion of a single cycle'of vibration thereof, saidvariations controlled by said device for indicating the-weight of the material carried bysaid structure, said device including: to the degree of deflection of said support fIOIIl ltS neutral position-when-- an electrical circuit which is responsive vibrated, and a condenser connected to said-circuit'to receive a variable charge conforming to the time required for said structure to traversesaid predetermined" said indicator includ portion-of one cycle of vibration, ing avoltrneter connected to said condenser and a source of predetermined voltage connected to said voltmeter, said condenser and-said source of-predeterminedvoltage being so connected 'to said voltmeter that diiferences inoutput thereof 'will be indicated on-the voltmeter.

structure adapted to vibrate when deflected from 8.11811- tral position, said structure being adapted to-support'material to beiweighed, and'means' structure to permit vibration thereof through a-single c-yg cleof vibration, said means including. an armatureconnected'to saidstructure, an .eiectromagnet adapted when energized to attract said armature and maintain said structure in 'adeflected position, an electrical circuit norto permitsaid structure to vibrate through one cycle of vibration, said controloperatingto reenergizesaid circuit.

whensaid armature reengages said electromagnet atthe. end of 'onecycle ofvibration of saidstructure whereby, said structure will again position.

4. In a weighing apparatus, the combination with-a; of taut primary strings-securedto:

frame, of .a plurality one section of said frame, a vertical member adaptedto. support an object to be weighed, said primary strings being .securedto one side of said membena secondary string secured to the. otherside of said member, and" a, spring connected to said of saidframe opposite to the section to which the primary strings are secured whereby said member is resiliently supported from said frame, and a device adapted to maintain said member in a deflected position and release said member to permit vibration thereof.

5. In a weighing apparatus for rapidly weighing cigarettes, the combination with a vibratory device adapted,

to vibrate when. deflected from a neutral position, ,a sup.- port carried by said'device and adapted'to support individual cigarettes to be weighed whereby variations in the weight of the cigarettes placed on said support will vary the vibration frequency of. said device, mechanism for.

deflecting said device from a neutralposition and releas-- ing the same to permit asingle cycle ofvibrationthereof for each cigarette placed on said support andmeansfon measuring the time required to complete a portion ofa.

single vibration of said device when supporting thev weight. of the cigarette placed on said support.

6. In a weighing apparatus, the combination with.a

vibratory device adapted to vibrate when deflected from.. a neutral position, a support carried by said deviceandj tion thereof each time material to be weighed ,is placed: on said support, and an instrument for determiningtthe time; interval between the moment saiddevice crosses said neutral position and returnsto .said neutral position in thesame'cycle .of .YibIaUOIL.

being created by variations inmthes: weight ofthe materialbeing weighed, and an indicator" 3. In a weighing apparatus, the combir'iationwithay v g for maintaining'saidi structure in a deflected position and then releasing said mally energizing.Saideltctromagnet, andla controlfor.

breaking said circuit and. deenergizing. said electromagnet be maintainedfin a deflected.

secondary string, and. a section.

7. In a weighing apparatus, the combination with a structure adapted to vibrate when deflected from a neutral position, a support on said structure adapted to carry material to be weighed whereby variations in the mass of the material supported thereon will vary the period of vibration thereof, means for deflecting said structure from its neutral position and releasing the same to permit a single cycle of vibration thereof each time material to be weighed is placed on said support, a device responsive to variations in the time required by said structure to complete a predetermined portion of a single cycle of vibration thereof, said variations being created by variations in the weight of the material to be weighed, and an indicator controlled by said device for indicating the weight of the material carried by said structure.

8. In a weighing apparatus, the combination with a structure adapted to vibrate when deflected from a neutral position, a support on said structure adapted to carry material to be weighed whereby variations in the mass of the material supported thereon will vary the period of vibration thereof, means for deflecting said structure from its neutral position and releasing the same to permit vibration thereof, a device responsive to variations in the time required by said structure to complete a predetermined portion of a single cycle of vibration thereof, said variations being created by variations in the weight of the material being weighed, said device including an electrical circuit which is responsive to the degree of deflection of said support from its neutral position, a

condenser connected to said circuit to receive a variable charge conforming to the time required for said structure to traverse said predetermined portion of one cycle of vibration, and an indicator controlled by said device for indicating the weight of the material carried by said structure.

9. In a weighing apparatus, the combination with a structure adapted to vibrate when deflected from a neutral position, a support on said structure adapted to carry material to be weighed whereby variations in the mass of the material supported thereon will vary the period of vibration thereof, means for deflecting said structure from its neutral position and releasing the same to permit vibration thereof, a device responsive to variations in the time required by said structure to complete a predetermined portion of a single cycle of vibration thereof, said variations being created by variations in the weight of the material to be weighed, said device including an electrical circuit, a pair of primary coils connected to said electrical circuit, a pair of secondary coils, an electrically conductive shield supported on said structure and extending between said primary and secondary pairs of coils, and an indicator controlled by said device for indicating the weight of the material carried by said structure.

10. In a weighing apparatus, the combination with a vibratory device adapted to vibrate when deflected from a neutral position, a support carried by said device and adapted to carry material to be weighed where by variations in the mass of the material carried on said support will vary the vibration frequency of said device, mechanism for deflecting said device from a neutral position and releasing the same to permit vibration thereof, and means for determining the time it takes to make two successive passes over said neutral position, said means including an electric circuit responsive to the degree of deflection of said device from its neutral position and a condenser connected to said electric circuit, said electric circuit operating to impose a single saw tooth wave of electrical current on said condenser.

11. In a weighing apparatus, the combination with a vibratory device adapted to vibrate when deflected from a neutral position, a support carried by said device and adapted to carry material to be weighed whereby variations in the mass of the material carried on said support will vary the vibration frequency of said device, mechanism for deflecting said device from a neutral position and releasing the same to permit vibration thereof, and means for determining the time it takes said device to make two successive passes over said neutral position, said means including a source of light, a photoelectric cell arranged to receive a beam of light from said light source, a shutter connected to said device and adapted to obstruct said light beam when said structure is deflected from its neutral position, and an electric circuit connected to said photoelectric cell and responsive to variations in the illumination of said photoelectric cell flected from a neutral position,

'10 produced when said device is released by said mechanisrn.

12. In a weighing apparatus, the combination with a vibratory device adapted to vibrate when deflected from a neutral position, a support carried by said device and adapted to carry material to be weighed whereby variations in the mass of the material carried on said support will vary the vibration frequency of said device, mechanism for deflecting said device from a neutral position and releasing the same to permit vibration thereof, and means for determining the time it takes said device to make two successive passes over said neutral position, said deflecting mechanism including an armature on said device, an electromagnet adapted when energized to attract said armature and maintain said device in a deflected position, an electrical circuit normally energizing said electromagnet, and a control for breaking said circuit and deenergizing said electromagnet to permit said device to vibrate through one cycle of vibration, said control operating to reenergize said circuit when said armature reaches said electromagnet at the end of one cycle of vibration of said structure.

13. In a weighing apparatus, the combination with a primary structure adapted to be vibrated when deflected from a neutral position, of a secondary structure adapted to be vibrated when deflected from a neutral position whenever said primary structure is vibrated, a support on said secondary structure adapted to carry material to be weighed and to vibrate therewith, said secondary structure having approximately the same vibration frequency as said primary structure when material of a predetermined mass is carried on said support whereby variations in the mass of the material to be weighed on said secondary structure will change the vibration frequency of said secondary structure relatively to the vibration frequency of said primary structure, means for deflecting both of said primary and secondary structures from their neutral positions and releasing them to permit a single vibration thereof, and instrumentalities for determining the time it takes each of said structures to make two successive passes over said neutral position and automatically comparing the difference in time be tween the two structures to determine the weight of the material supported on said secondary structure.

14. In a weighing apparatus, the combination with a primary structure adapted to be vibrated when deof a secondary structure adapted to be vibrated when deflected from a neutral position whenever said primary structure is vibrated, a support on said secondary structure adapted to carry material to be weighed and to vibrate with the material, said secondary structure having approximately the same vibration frequency as said primary structure when ma terial of a predetermined mass is carried on said support whereby variations in the mass of the material to be weighed on said secondary structure will change the vibration frequency of said secondary structure relatively to the vibration frequency of said primary structure, means for deflecting both of said primary and secondary structures from their neutral positions and releasing them to permit a single vibration thereof, a control for simultaneously releasing said primary and secondary structures at their deflected positions to permit a single simultaneous vibration thereof for each article that is weighed and means for determining the time it takes each of said structures to make two successive passes over said neutral position and automatically comparing the difference in time between the two structures to determine the weight of the material supported on said secondary structure.

15. In a weighing apparatus, the combination with a primary structure adapted to be vibrated when deflected from a neutral position, of a secondary structure adapted to be vibrated when deflected from a neutral position whenever said primary structure is vibrated, a support on said secondary structure adapted to carry material to be weighed and to vibrate therewith, said secondary structure having approximately the same vibration fre quency as said primary structure when material of a predetermined mass is carried on said support whereby variations in the mass of the material to be weighed on said secondary structure will change the vibration fre quency of said secondary structure relatively to the vibration frequency of said primary structure, means for deflecting both of said primary and secondary structures from their neutral positions and releasing them to permit r a singlewibration-ithereof for :each Zamountmf amaterial placed on said support, and instrumentalities zf-for measuring the time required for each i of said aprimary of a single-zcycle of: said vibration whereby the weight of the materiala carried: on sai'd :support on .the secondary structure .oan bew'compared' withs thexknown ,weightzof the :primary. structure; said instrumentalities' including a and vibrate with the:materialg'means fortmaintaining said structures in a deflected' position=and then releasing said primary structure 1 and- 'said secondarystructure and the material 'supported thereby to permit vibrat-ion of said structures and material through a single'cycle of vibration, and means for measuring the timeit-takes said secondary structure to completezoneportion ofa-single cycle of vibration and automatically-- comparing it to thetimeit takes the primary structure:to=complete one portion of a single cycle of vibration to determine-"the weight ofthe material supported 'on said secondary structure.

17. In a :weighing apparatus,the combination with a primary and, a secondary structure adapted to vibrate when deflected from a neutral position, said secondary structure being adapted to 1 support material: to -be weighed and'to vibrate-therewith,-and means for maintaining said primary: and secondary-structures in a deflected position and then releasing-said structures to permit vibration :thereof through :a :single'cycle of :vibration, mechanism fordelivering: an object tobe' weighedto said secondary structure while it is maintained in a deflected position,

by said means and thenrem'oving-"saidobjectfrom said secondary structure after thelatterhas-vibrated through one cycle of vibration and a de'vice formeasuring the time it takes said tprimary and secondary structures to complete aportion of each cycle ;'of vibration to determine the weight -of theobjectzsupported on said structure through athe-difference in=vibration time between both structures;

18.In" a weig'hing -apparatus, the combination with a primary structure adapted to -be i vibrated when 1 deflected froma neutral position; of a secondary structure adapted to be -vibrated= when deflected froma 'neutral position whenever 'saidprimary structure is vibrated, a support on said secondary structure 'adapted to carry material to' be weighed -and to vibrate therewith, said secondary structure" having approXimately thesame' vibration frequency as saidprimary structureflwhen material of a ."tures ifromstheirrneutral positions and fre'leasin'ge them itopermitia single vibration thereof;and instrumentalities fora-measuring -the time 1 required iforiisaid rprimary and secondary 'i'stru'ctures to kpass back. and forth cover isaid neutral positions wherebyihe weight'of the material carried'onisaid isupport' ontthe secondary structure can' 'be compared with thexknown tweight 'ofzthe primary 'stru'cture, and mechanism 'for delivering an :ob'jectr-to be weighed to r said secondary structure while -.the :l'at-ter is maintained in (a, :defleete'd 'position' 'by ':said means' and athenr removing said object from: said '=secon'dar'y structure after thelatter thasnret-urned to its 'deflectediposition.

19. In aiweighing apparatus, the-.combination with a 1 primary structure adapted to be vibrated when deflected from a neutral 1 position; of a secondary-structure adapted to be vibrated when "deflected": from 1 a neutraliz position whenever r'said .primary structure :is vibrated, ansupport on: said secondary structure=adapted-to carry material to be weighed and to vibrate :therewith; $said :secondary structure; having approximately the :same vibration frequency was said primary :structure'when material ofi'a predetermined mass :is carried .on saidxsupport :whereby variations in the massof the material to' beweighed-on said secondary r-structure will changethe vibration *frequency of said secondarypstructure relatively: to :the vibration frequency of said: primary structure; means for defleeting-both of-"said primaryand secondary.- structures from their neutral positions and releasing them toipermit -one cycle of =vibration thereof for each quantity of material weighed, and'instrumentalities for measuring thetime required foreach of-saidTprimary :an'd secondary structures 3 to acomplete :acertain portion :of a single. cycle of vibration whereby the weight of the material vcarried on and vibratedwith said support'on the secondary structure can 'be-comparedwitkthe known'weight of the primary structure by-v :measuring the: time difleren'cerfor each structure to complete the' certainportion of, a'single cycle of vibration, and mechanism; for regulating the vibration frequency of :each'of said primary and'secon'dary structures.

References'Cite'tl in thexfile' of this patent UNITED STATES PATENTS Number Name I Date 1,995,305 Hayes Mar. 26, 1935 2,077,390 Blau -Apr. 20; 1937 2,102,317 Gwinn Dec. 14, 1937 2,265,011 Siegel -5. Dec. 2, 1941 2,305,783 Heymann 'et a1. Dec.- 22, 1942 2,306,137 Pabst etaal. Dec. 22, 1942 FOREIGN PATENTS Number Country Date' 105,798 "Australia t. Nov. 10, 19.38 

